Wire twisting device

ABSTRACT

A device for forming a twisted pair of wires comprises a rotatable supply spool mounted above a stationary supply spool with the rotatable spool having an axial opening for permitting the passage therethrough of the wire from the stationary spool to a take-up reel or cabling device. The rotatable supply spool is driven at a predetermined angular velocity relative to the rate of the take-up device to provide the desired degree of twist. Coaxially mounted above the upper flange of each spool is a round disk which is slightly larger than the flange and is rotatable to provide unwinding of the wire from the spool and around the flange in a substantially constant-tension manner. Each spool is also provided with a hub coaxially mounted above the disk and having resilient spokes extending radially therefrom to provide a substantially uniform tension.

United States Patent 1 Orlandi Oct. 9, 1973 WIRE TWISTING DEVICE Primary Examiner-Lowell A. Larson 15 Inventor: John F. Orlandi, Lombard, 111. Anders [73] Assignee: Belden Corporation, Chicago, Ill. 22 Filed: Jan. 26, 1972 [57] ABSTRACT [2]] Appl. No: 220,866 A device for forming a twisted pair of wires comprises a rotatable supply spool mounted above a stat1onary supply spool with the rotatable spool having an axial [52] US. Cl. 140/149, 57/59 opening for permitting the passage therethrough of the Int. Cl. wire from the stationary spool to a [ake-up reel of caof sQIl'ch device The rotatable supply spool is driven at 3 1 59, 64 predetermined angular velocity relative to the rate of the take-up device to provide the desired degree of Rflelellces Cited twist. 'Coaxially mounted above the upper flange of UNITED STATES PATENTS each spool is a round disk which is slightly larger than 3,360,919 1/1968 Burr 57/59 the flange and is rotatable Provide unwinding of the 3,451,205 6/1969 T 57 1g wire from the spool and around the flange in a sub- 3,632,062 1/1972 Sole 242/147 stantially constant-tension manner. Each spool is also 2,206,494 7/1940 Alderfer 57/18 provided with a hub coaxially mounted above the disk 2,365,661 12/1944 Winslow l40/149 and resilient pokes extending radially therefrom to provide a substantially uniform tension.

2 Claims, 1 Drawing Figure 'eration.

- 1 WIRE TWISTING DEVICE I The present invention relates to wire-twisting apparatus and particularly to such apparatus for forming a uniformly twisted pair of wires as part of a cabling op- One particular problem in making twisted wire, either in a single operation or when combined with a cabling operation, is that of maintaining a substantially uniform tension on the supply wires so that the twist obtained is relatively uniform. The twisting is often desirable for insulated wires in the manufacture of telephone communication wires (often referred to as twisted pairs) or cables. Twisting the wires tends to improve the strength, attractiveness, and ease of handling of the end product; thus, a uniform twist is generally desired to optimize these characteristics. Moreover, for telephone communication lines or the like, twisting the wires also tends to balance the electromagnetic effects of the current passing therethrough to thus minimize crosstalkand other such phenomena.

Wire-twisting devices are generally classed into two basic types: l those in which one or more of the supply spools are rotated to provide the desired twist, (2) those in which the take-up means is rotated to provide the desired twist. It is often easier to obtain the desired twist by rotating one of the supply spools rather than the take-up means because the latter tends to be heavier and more cumbersome. In general, in a cabling operation wherein a relatively large cable is made from a plurality of twisted pairs, it is not practical to use existing equipment to perform the wire-twisting and cabling operations in one continuous process because of the relatively excessive floorspace and expense required thereby.

It is therefore an object of the invention to provide an improved wire-twisting device which is economical to manufacture.

It is another object of the invention to provide such an improved device which provides a uniform twist and occupies a minimum amount of floor space.'

Other objects and advantages of .the invention are more particularly set forth in the following detailed description, and in the accompanying drawings, the single FlGURE'of which is a front elevational view of a wiretwisting device constructed in accordance with the invention.

With reference to the FIGURE, there is shown a device constructed in accordance with the invention for forming a unifonnly twisted pair of wires as part of a continuous operation for fabricating a cable comprising a plurality of twisted pairs. In general, device 10 comprises a stationary supply spool for carrying one of the wires 21 to be twisted. Spool 20 has a central axis 22 oriented in a substantially vertical position and an upper wire-confining flange 23 of a given diameter. A round ring or disk 24 having a diameter greater than that of flange 23 is rotatably mounted coaxially with spool 20 above flange 23 for guiding wire 21 past flange 23 in a substantially constant-tension manner as described below in greater detail. A hub 25 having a pluv rality of resilient spokes 26 extending radially therefrom (the hub/spoke combination sometimes referred to as a whisker disk) is mounted coaxially with spool 20 near disk 24 for adding a relatively uniform amount of tension to wire 21 as also described in greater detail below. A rotatable supply spool 30 is provided for cartying the second wire 31 and is coaxially mounted above stationary spool 20. Similar to stationaryspool 20, rotatable spool 30 has an upper wire-confining flange 33 of a given diameter, a round disk 34 having a diameter greater than that of flange 33 and rotatably mounted coaxially with spool 30 above flange 3,3, and a hub 35 having a plurality of resilient spokes 36 extending radially therefrom and mounted coaxially with spool 30 near disk 34. Unlike stationary supply spool 20, however, rotatable supply spool 30 is adapted to be driven at a predetermined angular velocity relative to the take-up rate of a take-up means 50 by a driving device such as a motor 40 which may be coupled to both spool 30 and take-up means 50 by a shaft variable speed control and a suitable pulley system, gear train, etc. The particular construction of take-up means 50 forms no part of the invention and therefore is not discussed in great detail. Generally, greater advantage of the invention may be taken when take-up means 50 is a cabling device, although if desired the cabling device may be replaced by a simple take-up reel. In addition, spool 30 (shaft 70), disk 34, and hub 35, each have an axial opening therethrough to provide a passageway for wire 21 from stationary supply spool 20. Thus, as cabling means 50 unwinds the wire from supply spools 20 and 30, the rotation of spool 30 causes wire 31 to twist around wire 2'1 to thus form a twisted pair at the eyelet 51 of cabling device 50.

Referring to the FIGURE more particularly, wire 21 is unwound from stationary spool 20 over the curved outer edge of disk 24 through the spokes 26 of hub 25 and up through the axial openings of rotatable spool 30 (shaft 70.), disk 34, and hub 35 to eyelet 51 of take-up means 50. As wire 21 unwinds from. spool 20, the tension thereof ordinarily fluctuates due primarily to the angle at which wire 21 meets the curved edge of disk 24, the angle being more acute (thereby increasing wire tension) when wire 21 is unwinding from the top of spool 20 than that when it is unwinding from the bottom. Sometimes the tension varies due to various other factors such as the friction coefficient of the wire or any insulation thereon, the manner in which the wire was wound upon the spool, ambient temperature and humidity, etc. To substantially eliminate the nonuniformities in the twist of the wire often caused by non-uniform wire tension, the device of the invention provides rotatable disk 24 to guide wire 21 past upper flange 23. When the tension in wire 21 is relatively small, it slides around the curved portion of disk 24. When the tension increases to a predetermined level, however, the friction between wire 21 and disk 24 increases to cause disk 24 to rotate, thereby decreasing the wire tension to a level below the aforementioned predetermined level. This action is repeated as often as necessary to thus maintain the tension in wire 21 within a tolerance range such that, for practical purposes, the tension is substantially constant. The predetermined tension level is determined according to the amount of friction between rotatable disk 24 and its bearing surface, illustrated here as a bearing shaft 60 placed in the central axial opening 27 of spool 20, which opening is commonly found in conventional spools of wire. The amount of friction is controlled by the particular lubricant employed and/or the machine tolerances of the parts. It is understood that the particular manner in which disk 24 is rotatably mounted relative to spool 20 forms no part of the invention and may therefore be implemented in any suitable manner. Hub 25 is fixedly mounted to spool 20. in a manner such that resilient spokes 26 present a predetermined amount of friction to wire 21 in order to add a relatively uniform amount of wire tension. Spokes 26 are made from a resilient material such as nylon and bend as wire 21 unwinds to permit the wire to pay'off spool 20 but with a predetermined amount of friction to add a uniform amount of tension to wire 21. For a range of wire sizes there is a specified number of resilient spokes 26 of a given diam- V eter required for obtaining the proper tension. Generally for the heavy size wires where more tension is required there will be more spokes of a larger diameter and for finer size wires where less tension is required there will be less spokes of a smaller diameter.

The operation of rotatable supply spool 30 is similar to that of stationary supply spool 20 except for the fact that spool 30 is rotated at a predetermined angular velocity by motor 40. By controlling the angular velocity of rotatable supply spool 30 relative to the take-up rate of cabling device 50 (as, for example, by using motor 40 to drive both the spool, through variable speed control 45, and cabling device 50), wire 31 is twisted around wire 21 at a rate that provides the desired twist or lay." Disk 34 and hub 35 with resilient spokes 36 operate in a manner similar to disk 24 and hub 25 with resilient spokes 26 of spool 20 to provide a relatively constant tension in wire 31. As illustrated, spool 30 is mounted on hollow shaft 70, and anchored thereto by a pin 72, which is driven by motor 40. Disk 34 is rotatably attached to shaft 70 with suitable friction therebetween similar to disk 24 of spool 20. Hub 35 with resilient spokes 36 is fixedly mounted on the top of shaft 70 to add a relatively uniform amount of wire tension similar to the hub/spoke structure of spool 20. Again, as with spool 20, the mounting of spool 30, disk 34, and hub 35 may be implemented in any suitable manner. It should be noted that tension differences between wires 21 and 31 and may be further reduced by mounting spools 20 and 30 symmetrically relative to eyelets 71 and 51, respectively. Furthermore, eyelets 71 and 51 may preferably be made bell-shaped as shown to minimize friction.

Thus, there has been shown and described an improved wire-twisting device which provides a uniform twist and occupies a minimum amount of floor space. The device is relatively simple to construct and therefore economical to manufacture. Moreover, practically any desired number of devices constructed in accordance with the invention may be used to make twisted pairs for a multi-line cable in a single continuous operation that tends to reduce the cost of manufacturing the cable. Additional space saving in a vertical direction is afforded by the invention in that the eyelets may be mounted much closer (e.g., a spacing of one foot instead of three to four feet) to their respective spools because the relatively sharp angle created thereby no longer is a source of additional, tension-increasing friction.

It will, of course, be understood that modifications of the present invention, in its various aspects, will be apparent to those skilled in the art, some being apparent only after study, and others being merely matters of routine design. As such, the scope of the. invention should not be limited by the particular embodiment and specific construction herein described, but should be defined only by the appended claims, and equivalents thereof.

Various features of the invention are set forth in the following claims.

What is claimed is:

l. A device for forming a uniformly twisted pair of wires, comprising:

a stationary supply spool for carrying a first one of said wires and having its central axis orientated in a substantially vertical position and also having a first upper wire-confining flange of a given diameter;

a first round disc having a diameter greater than that of said first flange and rotatably mounted coaxially with said spool above said first flange, said first disc being engageable with said first wire to provide sole guidance there for to maintain said first wire in substantially constant tension as said first wire is drawn off of said stationary spool;

a rotatable supply spool for carrying the second one of said wires and coaxially mounted above said stationary spool and having a second upper wireconfining flange of a given diameter, said rotatable spool further having an axial opening therethrough;

a second round disc having an axial opening therethrough and being rotatably mounted coaxially with said rotatable spool above said second flange, said second disc having a diameter greater than that of said second flange and being engageable with said second wire to provide the sole guidance therefor to maintain said second wire in substantially constant tension as said second wire is drawn off of said rotatable supply spool;

take-up means for receiving both said first wire from said stationary spool through said axial openings and said second wire from said rotatable spool at a predetermined rate;

and means for driving said rotatable supply spool at a predetermined-angular velocity relative to the rate of said take-up means to obtain a desired wire twist.

2.'A device according to claim 1, which further comprises a first hub having at least one resilient spoke extending radially therefrom and fixedly mounted coaxially with said stationary spool near said first round disk for adding a relatively uniform amount of tension to said first wire; and a second hub having an axial opening therethrough and at least one resilient spoke extending radially therefrom, said second hub fixedly mounted coaxially with said rotatable spool near said second disk for adding a relatively uniform amount of tension to said second wire. 

1. A device for forming a uniformly twisted pair of wires, comprising: a stationary supply spool for carrying a first one of said wires and having its central axis orientated in a substantially vertical position and also having a first upper wire-confining flange of a given diameter; a first round disc having a diameter greater than that of said first flange and rotatably mounted coaxially with said spool above said first flange, said first disc being engageable with said first wire to provide sole guidance there for to maintain said first wire in substantially constant tension as said first wire is drawn off of said stationary spool; a rotatable supply spool for carrying the second one of said wires and coaxially mounted above said stationary spool and having a second upper wire-confining flange of a given diameter, said rotatable spool further having an axial opening therethrough; a second round disc having an axial opening therethrough and being rotatably mounted coaxially with said rotatable spool above said second flange, said second disc having a diameter greater than that of said second flange and being engageable with said second wire to provide the sole guidance therefor to maintain said second wire in substantially constant tension as said second wire is drawn off of said rotatable supply spool; take-up means for receiving both said first wire from said stationary spool through said axial openings and said second wire from said rotatable spool at a predetermined rate; and means for driving said rotatable supply spool at a predetermined angular velocity relative to the rate of said take-up means to obtain a desired wire twist.
 2. A device according to claim 1, which further comprises a first hub having at least one resilient spoke extending radially therefrom and fixedly mounted coaxially with said stationary spool near said first round disk for adding a relatively uniform amount of tension to said first wire; and a second hub having an axial opening therethrough and at least one resilient spoke extending radially therefrom, said second hub fixedly mounted coaxially with said rotatable spool near said second disk for adding a relatively uniform amount of tension to said second wire. 